2000 Yukon-Long warm up time - partial heater core restriction possibly?

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UmmScott

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Trying to get an idea for what the typical time it takes while driving to get the engine up to temp.
My 2000 yukon seems to take a while to get up to 195 at least and the heater performance kinda sucks especially at idle.
Its been in the upper 10's to upper 20's here lately.
I actually think I have either a combination of 2 small problems or just a partially plugged heater core. If I drive roughly 7 miles to get to the highway usually going 45mph with the occasional stops (so about 12 mins). The temp gauge just gets to the 1/4 mark. Generally have the rear and front blower on high and temp all the way high.

Just never really gets good and warm in the truck. Its barely mild at best. Temp gauge does get up to the 195 right before 210 mark just takes a long time. Heat in city traffic sucks, you can feel the vent temps cool off when at idle and they warm back up when accelerating.
There really isnt any good heat until it finally gets to 195.
I think the heater core is the issue, perhaps partially plugged? Coolant level is good, there are no leaks. Thermostat was replaced by previous owner and there are records of the heater core being flushed and it states in the records that he's had this lack of heat issue a few times
What do you guys think? how long does warm up typically take for your truck?
 

OR VietVet

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The heater core will not keep an engine from coming up to temp as fast as it should. I suspect the thermostat. Last owner replaced WHEN? You could also have a problem with the incorrect radiator being in the rig. Threads here about that. Put a piece of cardboard in front of the grill and drive in your neighborhood and see if the temp comes up quicker and blows hotter. e prepared to stop and remove cardboard.
 

Fless

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@UmmScott, I agree with @PNW VietVet that a plugged heater core wouldn't keep the engine from warming up. It sounds like the thermostat's been replaced, but is it the right one?

Any chance the radiator's been replaced? The OEM radiators have a restriction in the small return line going to the surge tank, and many of the aftermarket ones don't have it. You could pinch that hose off a little (not all the way) to see if that's the problem.

There are several threads on that problem, here's one:
https://www.tahoeyukonforum.com/thr...to-normal-operating-temp.109849/#post-1311191
 

BG1988

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Trying to get an idea for what the typical time it takes while driving to get the engine up to temp.
My 2000 yukon seems to take a while to get up to 195 at least and the heater performance kinda sucks especially at idle.
Its been in the upper 10's to upper 20's here lately.
I actually think I have either a combination of 2 small problems or just a partially plugged heater core. If I drive roughly 7 miles to get to the highway usually going 45mph with the occasional stops (so about 12 mins). The temp gauge just gets to the 1/4 mark. Generally have the rear and front blower on high and temp all the way high.

Just never really gets good and warm in the truck. Its barely mild at best. Temp gauge does get up to the 195 right before 210 mark just takes a long time. Heat in city traffic sucks, you can feel the vent temps cool off when at idle and they warm back up when accelerating.
There really isnt any good heat until it finally gets to 195.
I think the heater core is the issue, perhaps partially plugged? Coolant level is good, there are no leaks. Thermostat was replaced by previous owner and there are records of the heater core being flushed and it states in the records that he's had this lack of heat issue a few times
What do you guys think? how long does warm up typically take for your truck?
my old impala was at operating temp with in 2min of driving heater was nice and toasty had to open the window as it was too hot
 
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UmmScott

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Thanks guys.
I will double check about that hose for sure.

The heater hoses never get really all that hot. I can hold onto them all day long.

Will post what i find

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OR VietVet

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If you can hold at least one of the hoses from the heater core then it is getting plugged but if they both are the same temp then then the heater core is likely not plugged. It could be restricted but not completely plugged. But, it has nothing to do with the engine temp.
 
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UmmScott

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Right. I gotcha and understand that. I will see what i find

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BG1988

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But then again all of your vehicles seem to have magical powers.
it's true it was warmed up once I got to the main street down the road 2 min away plus 1 min closing the gate

electrical A/Cs can in fact cool faster then a normal mechanical A/C.. is that what your mad about?
nothing magic about it it has way higher cooling capacity then a mechanical A/C.. there for can cool faster.. how is it magic when it takes less 30 seconds to start pouring out cooler air while your mechanical a/c takes much longer as it has less capacity and takes longer to circulate the tube to the rear a/c why do you think it takes 3-4min? to start cooling down?



which has more POWER then a cheap belt driven a/c can do


also btw this Tahoe takes forever to warm up if that matters to you as there is nothing on the pulley(except for a water pump) to add additional load to the engine
 
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